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Abstract: Radiofrequency thermal ablation (RFTA) is a local tumor-destructing technique that can potentially modulate the host immune response through mechanisms that are not clearly defined. We assessed whether RFTA could affect multiple systemic inflammatory and immunological parameters, including CD25+Foxp3+ cells, in patients with primary or metastatic lung tumors. Three days after RFTA, a moderate and temporary systemic inflammatory response developed, as demonstrated by the increase in peripheral neutrophils and monocytes and in plasma levels of proinflammatory chemokines (MIP-1α, MIP-1β, eotaxin, and interleukin[IL]-8) and acute phase reactants (complement C3 and C4, serum amyloid, α1 antichymotrypsin, and C-reactive protein). Moreover, we found a concomitant release of the anti-inflammatory factor IL-10. Thirty days after RFTA, a significant reduction in CD25+Foxp3+ counts with an increase in CD4+ T-cell proliferation and number of interferon-γ-secreting cells was observed. The reduction in CD25+Foxp3+ cells lasted up to 90 days after treatment. The use of RFTA in lung cancer patients has an immunomodulatory activity: it induces a self-limiting systemic inflammation early and later a reduction of circulating CD25+Foxp3+ Tregs. In addition to tumor ablation, downmodulation of this regulatory subset might be an important mechanism involved in the long-term clinical efficacy of RFTA. [Copyright &y& Elsevier]

Abstract: The role of T regulatory (Treg) cells in human cancer has not yet been clarified. We assessed the presence and function of CD4+ and CD8+ Treg cell subsets in the peripheral blood of patients with lung cancer (LC) and pleural mesothelioma (PM). We found a low but significant increase in the number of CD4+ T cells with phenotype and functional features of Treg cells in LC patients compared to normal healthy controls (NHC). Furthermore, total CD4+ T cells from LC patients proliferated less than cells from controls, suggesting that the increase in the CD4+ Treg cell pool has functional importance. LC patients also showed an expansion of the CD8+CD28− T cell subset and these cells expressed Foxp3 mRNA, as recently observed in alloantigen-specific CD8+CD28− T suppressor cells. No variation of peripheral Treg cell subsets was found in patients with PM, a disease with a predominantly localized nature. However, the lack of correlation between cancer stage and the number or the function of peripheral Treg cells in LC patients refuted the hypothesis that these cells are involved in tumor spreading. A possible involvement of the peripheral Treg cell pool in cancer development and/or in inducing systemic immunosuppression in LC patients can be hypothesized. [Copyright &y& Elsevier]

Signalling cascades involved in chemokine production by human phagocytes following infection withMycobacterium tuberculosis are still not defined. We used specific pharmacologic inhibitors to identify the signalling molecules which lead to interleukin (IL)-8 and MCP-1 production in human monocytes in response to M. tuberculosis infection. Inhibition of extracellular signal-regulated (ERK) or p38 mitogen-activated protein kinase by PD 98059 and SB 203580 respectively, significantly affected chemokine production. However, only the presence of both inhibitors completely blocked the release. A down-regulation of chemokine secretion was found in presence of inhibitors of protein kinase (PK)C and phospholipase C. Moreover, production depended on transcription activation via the nuclear factor-kappa B (NF-κB), as demonstrated by treatment with actinomycin D and caffeic acid phenethyl ester. In addition, activation of PKA and the phosphoinoside 3-kinase (PI-3k)/p70 ribosomal S6 kinase cascade was required to have maximal MCP-1 but not IL-8 production. In conclusion, this study provides evidence that multiple signal transduction pathways are involved in M. tuberculosis -induced chemokine secretion by human monocytes. Moreover, for the first time this report indicates that inhibitors of some signalling molecules are able to dissociate IL-8 from MCP-1 secretion. Differences in the regulatory pathways of chemokine production can potentially be exploited therapeutically. [Copyright &y& Elsevier]

In the airway tract acetylcholine (ACh) is known to be the mediator of the parasympathetic nervous system. However ACh is also synthesized by a large variety of non-neuronal cells. Strongest expression is documented in neuroendocrine and in epithelial cells (ciliated, basal and secretory elements). Growing evidence suggests that a cell-type specific Ach expression and release do exist and act with local autoparacrine loop in the non-neuronal airway compartment. Here we review the molecular mechanism by which Ach is involved in regulating various aspects of innate mucosal defense, including mucociliary clearance, regulation of macrophage activation as well as in promoting epithelial cells proliferation and conferring susceptibility to lung carcinoma onset. Importantly this non-neuronal cholinergic machinery is differently regulated than the neuronal one and could be specifically therapeutically targeted.

Interstitial pneumonites represent a heterogeneous group of respiratory disorders with known causes or idiopathic, in which alveolar injury is followed by defense and repair mechanisms either with pro- and anti-inflammatory properties. It is hypothetised that common factors would orchestrate such events, and RAGE is one of possible such candidates. Implications connected to RAGE pathway in varying interstitial pneumonites are discussed.

Background: Micro-organisms, behaving in a non-infectious fashion, may be among the exogenous factor(s) believed to trigger idiopathic pulmonary fibrosis (IPF). One possible strategy to identify an individual's susceptibility to such microbial triggers, which are likely to be ubiquitous, is to investigate the molecular processes involved in their recognition. NOD2/CARD15 is a specific pattern recognition receptor protein, whose genetic variants have been previously associated with susceptibility to Crohn's disease., Aim: The aim of this work was to determine the frequencies of the three major NOD2/CARD 15 gene mutations (R702W, G908R and 1007fsinC) in a series of 76 subjects affected by IPF, and to compare them with those found in three groups of controls: a group with sarcoidosis (a disorder in which an involvement of the NOD2/CARD15 gene has already been investigated and rejected in different ethnic groups; 67 subjects) and two groups of healthy subjects (218 and 208 subjects, respectively), matched for gender, age, and ethnicity., Results: We found no differences in frequencies of NOD2/CARD15 gene polymorphisms among the four groups investigated., Conclusion: We conclude that the NOD2/CARD15 gene is not likely to be involved in susceptibility to IPF in Italians.

Background and Aim: Fibrosing alveolitis develops in up to 80% of systemic sclerosis patients (SSc) but progression to end stage fibrosis occurs in about 15% of cases. Mechanisms leading to the process remain mostly unknown. We compared cytokine profiles of broncho-alveolar lavage fluids (BAL-f) from patients with SSc associated interstitial lung disease (SSc-ILD) (n. 34), idiopathic pulmonary fibrosis (IPF) (n. 13), stage II sarcoidosis (n. 14) and 9 controls., Methods: Interleukin (IL) 8, monocyte chemoattractant protein 1 (MCP-1), gamma-interferon (IFN-gamma), IL12, IL18 and IL10 and transforming growth factor-beta (TGF-beta) were assessed by ELISA in concentrated BAL-f., Results: Levels of IL8 and MCP-1 were significantly elevated in SSc-ILD and in IPF as compared with controls (Mann Whitney test p < 0.05), while MCP-1 values were significantly lower in SSc-ILD than in IPF. A significant correlation between neutrophils and IL8 levels (p = 0.047), as well as between eosinophils and MCP-1 levels (p = 0.004) was also observed. IFN-gamma levels were slightly higher than normal only in sarcoidosis (p = 0.06), whereas IL12 levels increased both in sarcoidosis and SSc-ILD (p < 0.05). No differences were found in IL18 and TGF-beta levels. Finally, IL10 levels were higher in SSc-ILD and sarcoidosis than in controls and IPF (p < 0.05)., Conclusion: BAL-f cytokine profile differentiates ILD associated with SSc from IPF. The lower expression of MCP-1 and the higher expression of the anti-fibrotic IL12 and the anti-inflammatory IL10, observed both in sarcoidosis and in SSc-ILD, could account for the better prognosis of these ILDs. Further longitudinal studies are required to confirm whether a different cytokine phenotype may be considered predictive of clinical outcome in SSc-ILD.